Machine for horizontally manufacturing flexible sheet material packagings with outside chamber

ABSTRACT

Machine for horizontally manufacturing flexible sheet material packagings, including an area for feeding a continuous web of flexible sheet material, a preforming area including an area for folding the bottom wall of said packaging and a welding area, an area for filling said packagings, an area for outputting said packagings, a first chemical decontamination treatment area using a gas, arranged between the preforming area and the filling area, and an outside chamber that surrounds said machine at least partially and is depressed with respect to said first area. The outside chamber acts as an additional barrier between the first area and the outside. 
     Outside chamber can be depressed also with respect to atmospheric pressure.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a machine for horizontally manufacturingflexible sheet material packagings, comprising

-   -   an area for feeding a continuous web of flexible sheet material,    -   a preforming area including an area for folding the packaging        and a welding area,    -   an area for filling the packaging,    -   an area for outputting the packagings, and    -   a first chemical decontamination treatment area using a first        gas that is chemically active as a decontaminating agent, where        the first treatment area is arranged between the preforming area        and the filling area.

2. Description of the Related Art

Various machines of the type indicated above are known. So, for example,document WO 2005/120960, published on 22 Dec. 2005, describes a machineof this type. For its part, document EP 1.743.839, published 17 Jan.2007, describes a machine that uses a gas to decontaminate the flexiblesheet material before it is preformed. Other similar machines aredescribed in documents EP 1.245.493, published 2 Oct. 2002, ES2.068.463, published 13 May 2002, ES 2.255.815, published 1 Jul. 2006,and ES 2.127.939, published 29 May 1996.

Nevertheless, there is a constant demand to increase the useful life ofpackaged goods, so that they can be stored for a longer time. Thisrequires increasing the quality of the decontamination and/or reducingthe risk of possible contamination after packaging.

Also, handling the decontamination gas is a complicated process asusually gases that are more or less toxic or irritant to the human bodyare used, and therefore there is also a permanent interest in improvingand facilitating the handling of the decontaminating gas and increasingthe safety of the machine operators.

SUMMARY OF THE INVENTION

The aim of the invention is to overcome these drawbacks. This aim isachieved by means of a machine of the type indicated at the beginning,characterised in that it comprises, in addition, an outside chamber thatsurrounds the machine at least partially and which is depressed withrespect to the first area.

In fact, these machines normally have at least one point for accessingthe inside thereof. These access points are necessary for severalreasons, such as for example for maintenance tasks, to solve machinestoppages for any unforeseen reason, etc. The access points have a dooror openable cover and a fitting frame where a normally airtight closureis established between the cover and the machine structure. These accesspoints always represent a risk of possible sources of contamination,both in the form of bacteria from the outside inwards, anddecontaminating agents from the inside outwards, which is a consequentrisk for the machine operator. In this respect, it is advantageous thatthe machine comprises an outside chamber that surrounds the machine atleast partially and which is depressed with respect to the first area.In fact, this way it is possible to create an additional barrier betweenthe inside of the machine and the atmosphere. Also, the main function ofthis outside chamber is to prevent the decontamination gases frompossibly leaking out into the atmosphere. Under these conditions, anypossible leakage of decontaminating gas is collected in the outsidechamber where it can be extracted by a corresponding pump or fan.Preferably the outside chamber is also depressed with respect toatmospheric pressure. This guarantees that there will be no leakage fromthe outside chamber to the outside. Preferably the depression of theoutside chamber with respect to the atmosphere is between 0 and 1000 Pa,and very preferably between 10 and 500 Pa.

It must be understood that by stating that the outside chamber surroundsthe machine at least partially, it is meant that it surrounds at leastone part of the machine comprising the fitting frame of an access point.In this respect, it must be taken into account that the outside chambercan only surround the fitting frame of one access point (or even onlyone part of the fitting frame), can surround the whole access point(both the fitting frame and the cover or door), or it can even surroundlarger parts of the machine, for example including several access pointsin one single outside chamber.

As can be seen, the basic function of the outside chamber is to avoidleakage problems with the access points. In this respect the outsidechamber can have various different geometrical shapes. In particular,the outside chamber can completely surround all the various accesspoints on the machine (one single outside chamber for all the accesspoints) or it can only surround some of them. In this latter case it maybe that there are other access points which, for whatever reason, do notneed an outside chamber or it may be that the machine has a plurality ofsecond chambers, to the extent that the machine could be fitted withsecond chambers consisting merely of double joint frames arranged aroundsome and/or each access point or the fitting frames proper.

Advantageously the machine has all its access points arranged on one andthe same side and the outside chamber surrounds the machine only on thisside. Effectively, grouping the access points in this way simplifies thegeometrical shape of the outside chamber.

Preferably the machine comprises, in addition:

a second chemical decontamination treatment area where the secondtreatment area is arranged before the preforming area,

an inside chamber that extends between the second treatment area and thefirst treatment area, with the inside chamber being full of a seconddecontaminating gas, where the second gas in the inside chamber is overpressurised with respect to atmospheric pressure, and preferably, wherethe outside chamber is also depressed with respect to the insidechamber.

Effectively, this way the decontamination carried out in the second areais maintained in optimum conditions, and the risk of a new contaminationoccurring when the sheet web moves through the preforming area isavoided. Also, since the second gas in the inside chamber is overpressurised with respect to atmospheric pressure it is guaranteed that,even if there is a leak or hole in the machine, atmospheric air willnever enter the inside chamber. This way the inside chamber is aninsulator with over pressurised decontaminating gas.

Furthermore, since the outside chamber is also depressed with respect tothe inside chamber, leakages of the second decontaminating gas outwardsare also avoided.

This way, another possible reason for having two second chambers couldbe if the first decontaminating gas and the second decontaminating gaswere different from one another. Then there could be an outside chambersurrounding the access points in the first area (and, possibly, thefilling and output areas) and another outside chamber surrounding theaccess points in the inside chamber (which will usually comprise thepreforming area), since it may be convenient to treat the possibleleakages of the first gas and the second gas in a different way.

Nevertheless, it must be noted that the outside chamber is advantageousboth if the inside chamber contains a decontaminating gas or notbecause, at any event, the first area will always contain the firstdecontaminating gas.

Advantageously the second chemical decontaminating treatment areaconsists in applying a chemically active decontaminating liquid to thesheet web. Effectively, using a chemically active liquid guarantees thatthe whole sheet web is treated. Also, using a liquid guarantees that agreater concentration of the decontaminating agent reaches each point ofthe sheet web. Applying the chemically active liquid to the sheet webbefore the preforming area means that it is applied to the sheet webwhen the latter is still completely unwound. Under these conditions, theliquid can reach all the points of the web much more easily than if theweb were folded, when corners and angles are formed that are difficultto access. Moreover, it is also easier to remove the liquid once thedecontamination has taken place. It must be taken into considerationthat using a liquid has the additional advantage that the liquid cleansby mechanically dragging all kinds of dirt, dust, etc. that may be onthe web, and this is impossible, or almost impossible to achieve with agas, considering the flow rates and pressures conventionally used inthis type of machines. Another additional advantage is that the liquidcan reach and, therefore, disinfect, small scratches that may appear onthe web, and which a gas current could not reach.

A preferable embodiment of the invention is obtained when the secondarea comprises a first submersion tank containing the liquid and firstguiding means that introduce the web into the tank so that the liquid isapplied by immersing the web in said liquid.

Alternatively, the second area comprises a first decontaminatingcompartment which houses first spraying means and first guiding meansthat introduce the web into the first compartment so that the liquid isapplied by spraying the liquid on to said web. This application could beperformed on only one of the web surfaces, specifically on the innersurface, which is the one that will have difficult to access corners andangles when the web is folded. Nevertheless, preferably the liquid isapplied to both web surfaces.

At any event, both solutions have the advantage that they do not affectthe machine's productivity, as the areas can be made longer or shorterdepending on the desired contact time with the decontaminating agentwithout affecting the machine cycle time.

In addition, it is particularly advantageous that the first gas in thefirst area is over pressurised with respect to the pressure in theinside chamber, as this way a flow is established extending from thefirst area to the inside chamber. It must be taken into account that thefirst area is just before the packaging filling area, where maximumseptic conditions must be observed. Generally, it is particularlyadvantageous that the first area be over pressurised with respect toatmospheric pressure as this minimises the risk of contamination throughcontaminated air entering the first area, either through possible accesspoints or through any other point that may have a hole or porosityconnected directly or indirectly with the atmosphere. Preferably theoverpressure in the first area with respect to atmospheric pressure isbetween 5 and 500 Pa, and very preferably between 10 and 100 Pa.

Both the first gas and the second gas must be chemically active asdecontaminating agents. This can be achieved in various ways, allcompatible with this invention. In practice, the most usual is thatthese gases consist of a mixture of various components, where at leastone of them is the real decontaminating agent, and the other componentsare essentially responsible for acting as a vehicle for transporting theactive components. Advantageously, the first gas and/or the second gascomprise H₂O₂ (hydrogen peroxide) in a gaseous state as thedecontaminating agent.

Also, the liquid must be chemically active as a decontaminating agent,which can also be obtained in various ways, all compatible with thisinvention. Also in the case of the liquid, it is often a mixture ofcomponents, where at least one of them is the real decontaminatingagent. As in the case of the gas, it is advantageous that the liquidcomprises H₂O₂ in a liquid state as the decontaminating agent.

Another advantageous embodiment of the machine according to theinvention is obtained when the second chemical decontamination treatmentarea employs a third gas that is chemically active as a decontaminatingagent, which, preferably, comprises H₂O₂ in a gaseous state. In thiscase, the whole machine performs the complete web decontaminatingprocess by gaseous means.

Preferably the decontaminating gases are produced in external equipment,so that the previously produced decontaminating gas is injected into themachine (in the first area and/or in the inside chamber and/or in thesecond area). This ensures a more uniform distribution than if adecontaminating liquid is sprayed inside the machine to evaporate and bedistributed inside the machine. Also, this system provides forregulating the concentration of decontaminating agent in thedecontaminating gas, so that in each case the desired concentration isapplied uniformly throughout the compartment in question.

Generally, the decontaminating gas is, inside the correspondingcompartment, at a temperature of between 40° C. and 70° C., particularlywhen the decontaminating agent is H₂O₂. For its part, thedecontaminating liquid is preferably at a temperature of between 40° C.and 80° C., particularly when the decontaminating agent is H₂O₂. In thisrespect, it must be understood that when it is stated that the gasesmust be chemically active as decontaminating agents, it must beunderstood that they must be chemically active as microbiologicaldecontaminating agents and within the range of temperatures between 40°C. and 70° C. Similarly, it must be understood that the decontaminatingliquid is chemically active as a microbiological decontaminating agentwithin the range of temperatures between 40° C. and 80° C. Also it mustbe clear that both hot air and water vapour are considered to beexcluded from this definition of decontaminating gas.

Usually the packagings have top stoppers. These stoppers are usuallyassembled onto the packaging once the latter has been filled with thecorresponding product. This stage of assembling the stopper onto thepackaging is usually performed in the same machine. In this respect itis advantageous that the machine comprises a third chemicaldecontamination treatment area that applies to said stoppers a secondliquid that is chemically active as a decontaminating agent.Effectively, this way the decontaminating (and mechanical cleaning)advantages are also applied via a liquid to the stoppers, whichincreases the extent of the unit's decontamination.

As in the case of the second chemical decontamination treatment area,the liquid can be applied by submersion or spraying. Therefore, apreferable solution would consist in the third area comprising a secondsubmersion tank that contains the second liquid and second guiding meansthat introduce the stoppers into the second tank so that the secondliquid is applied through submersion, whereas another preferablesolution would consist in the third area comprising a seconddecontamination compartment which houses second spraying means andsecond guiding means that introduce the stoppers into the secondcompartment so that the second liquid is applied by spraying it onto thestoppers. In either of the two cases, preferably the second liquidcomprises hydrogen peroxide as the decontaminating agent.

Advantageously, when the packagings comprise top stoppers, the machinecomprises an area for attaching the stoppers to the packaging, where thestopper attachment area, in turn, comprises a first area for preweldingthe stopper to the sheet material, a second area for welding the stopperto the sheet material and a third area for welding the sheet materialarranged on the sides of the stopper.

Another known way of decontaminating packagings is via ultravioletradiation (UV rays) of the sheet material web and/or the packaging inany of its formation stages. Logically, this method of decontaminationis completely compatible with this invention, and therefore it ispossible to include one or more UV radiation stages in any part of theprocess, such as for example in the preforming area. Also, the UVradiation step can be added to an area where there is no gas that ischemically active as a decontaminating agent or, on the contrary, it canbe added to an area where there is also a decontaminating gas, althoughin the latter case care should be taken to ensure that the UV rays donot negatively affect the decontaminating properties of the gas.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages and characteristics of the invention will beappreciated from the following description, which provides anon-limiting description of some preferable embodiments of theinvention, with reference to the accompanying drawings, in which:

FIG. 1, a diagrammatical front view, of a longitudinal section of amachine according to the invention.

FIG. 2, a diagrammatical perspective view, of a longitudinal section ofa second chemical decontamination treatment area according to theinvention.

FIGS. 3 a and 3 b, diagrammatical front views, of a second submersion(FIG. 3 a) and spray (FIG. 3 b) treatment area.

FIGS. 4 a, 4 b and 4 c, side views of cross-sections of the machine inFIG. 1 showing three possible alternative geometrical shapes of thesecond outside chambers.

FIG. 5, a perspective view, partially sectioned of a third chemicaldecontamination treatment area of the stoppers via spraying.

FIG. 6, a perspective view, partially sectioned of a third chemicaldecontamination treatment area of the stoppers through submersion.

FIG. 7, a perspective view of the sequence followed in a stopperattachment area according to the invention.

FIG. 8, a diagrammatic view of an outside chamber shaped with a doublejoint frame.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a machine for horizontally manufacturing flexible sheetmaterial packagings according to the invention. The machine has an area1 for feeding a continuous sheet material web 3. This web 3 is preformedin a preforming area 5 where it is folded so as to form the bottom wallof the packaging and the sides of the packaging are welded, after whichweb 3 is cut so that the packagings are separated from each other. Thenthe packagings enter a first chemical decontamination area 7 by means ofa first gas that is chemically active as a decontaminating agent, inparticularly a gas containing hydrogen peroxide. Once the packagings aredecontaminated, they are filled in the filling area 9, the stopper isadded and they are removed through the output area 11. The stopper, inturn, passes through a third chemical decontamination 13 treatment area.

First area 7 is full of the first gas and is over pressurised withrespect to the atmosphere. Between first area 7 and filling area 9 thereare closing means (a semi-closed wall) which, together with a suitablepressure difference, prevent the first gas from passing into fillingarea 9 (although air can pass from filling area 9 to first area 7).Filling area 9 is the most sterile area in the whole of the machine, butit can no longer contain gases that may be hazardous to health, andtherefore it is full of sterile air. Output area 11 has other closingmeans that prevent atmospheric air from entering. Between the preformingarea 5 and first area 7 there is a narrow passage. Preforming area 5 isalso over pressurised with respect to the atmosphere, but its pressureis lower than first area 7, so that a gas current flow is establishedextending from first area 7 to preforming area 5. This way preformingarea 5 defines an inside chamber 15 that extends throughout thepreforming area. In this case, the second decontaminating gas is thesame as the first decontaminating gas.

Between feeding area 1 and preforming area 5 there is a second chemicaldecontamination treatment area 17, where web 3 is immersed in a firstsubmersion tank 19 containing a decontaminating liquid that has hydrogenperoxide. First guiding means 21, consisting of some rollers, guide web3 through first tank 19. FIG. 2 shows this second area 17 in greaterdetail, where a reel 23 can also be seen, which carries web 3 offlexible sheet material to the machine. FIGS. 3 a and 3 b show acomparison between the alternative of using a first submersion tank 19or using a first decontamination compartment 25 with first sprayingmeans 27. Other means are possible for applying to web 3 the liquid thatis chemically active as a decontaminating agent, such as for exampleusing a liquid curtain. Generally any application method is suitable forthe general concept of the invention. Preferably inside chamber 15extends between second treatment area 17 and first treatment area 7. So,recently disinfected web 3 is not in contact at any time with theatmosphere or, generally, with a non-decontaminated environment.

Additionally, by using a first tank 19 the liquid bath proper can beused as an airtight barrier between inside chamber 15 and the outside.Effectively, by adding a divider that extends from the inner top part ofsecond area 17 and has its bottom end immersed in the decontaminatingliquid, it is possible to insulate inside chamber 15 and the part ofsecond area 17 adjacent thereto with respect to the part of second area17 adjacent to feeding area 1, and, therefore, with respect to theoutside.

With this embodiment, once web 3 has entered second area 17, at no timedoes it leave a sterile atmosphere, as the whole of the inside of themachine is in a decontaminated or sterile atmosphere. Consequently, infirst area 7 it is no longer necessary to inject the first gas insideeach preformed packaging (as normally occurs in the state of the artmachines), as instead it suffices that the first gas is injected insidefirst area 7 in a general manner.

The machine has a plurality of access points 29, needed to access insidethe machine to correct any incidents, machine stoppages, or maintenancetasks, etc. These access points 29 are usually distributed along thewhole machine, so that all areas of the machine can be accessed. FIGS. 4a, 4 b and 4 c show some resolution alternatives for access points 29.In FIG. 4 a access point 29 has an outside chamber 31 that only extendsalong the side of the machine. In FIG. 4 b, outside chamber 31 surroundsthe machine both on the side and the top therefore and in FIG. 4 coutside chamber 31 surrounds the machine on the side, top and bottomthereof.

FIGS. 5 and 6 show two alternative embodiments of the third chemicaldecontamination treatment area 13 for the stoppers. FIG. 5 shows how thestoppers are suitably selected and orientated by means of vibratingbowls 33 and then introduced into a second decontamination compartment35 which houses second spraying means that apply to the stoppers, viaspraying, a second liquid that is chemically active as a decontaminatingagent, normally an aqueous solution of hydrogen peroxide. For its part,FIG. 6 shows how the stoppers are introduced into a second submersiontank 39 that contains the second decontaminating liquid. In this case,the second guiding means 41 are a U-shaped guide that provides forintroducing the stoppers and removing them from the second tank 39.Following the submersion, there is a stopper aeration step, where thelatter are dried before being assembled onto the packagings. Both in thecase of application through spraying or submersion, it is advantageousthat the access points to this part of the machine have an outsidechamber.

As in the case of second chemical decontamination area 17, if a thirdchemical decontamination treatment area 13 is used for the stoppers,comprising a second submersion tank 39 the decontaminating liquid can beused as an air-tight barrier between the outside and the inside of themachine. Generally, it must be considered that, both in second area 17and in third area 13 using a submersion tank or using sprayers arenon-exclusive alternatives, and they can also be combined together.

FIG. 7 shows in detail the stages of attaching the stoppers to thepackagings. Stopper attachment area 43 comprises a first stopperprewelding area 45 where the stopper is preattached to the packaging, asecond stopper welding area 47 where the stopper is definitivelyattached to the packaging, and a third stage 49 for welding the sheetmaterial arranged on the stopper sides to the packaging. This sheetmaterial has been preheated during the stopper prewelding and weldingstages, and therefore it is strongly welded in one stage. Finally, thereis a fourth unit cooling stage 51, which is a conventional coolingstage.

FIG. 8 shows a diagrammatic view of an example of an outside chamber 31,shaped as a frame with two joints 53, arranged around one access point29 to inside chamber 15.

1. Machine for horizontally manufacturing flexible sheet materialpackaging, comprising: an area for feeding a continuous web of flexiblesheet material, a preforming area including an area for folding thebottom wall of said packaging and a welding area, an area for fillingsaid packaging, an area for outputting said packaging, a first chemicaldecontamination treatment area using a first gas that is chemicallyactive as a decontaminating agent, wherein said first treatment area isarranged between the preforming area and the filling area; and an outerchamber that surrounds said machine at least partially and is depressedwith respect to said first area.
 2. Machine according to claim 1,wherein said outer chamber is also depressed with respect to atmosphericpressure between 0 and 1000 Pa.
 3. Machine according to claim 1, furthercomprising: a second chemical decontamination treatment area where asecond treatment area is arranged before the preforming area; and aninner chamber that extends between said second treatment area and saidfirst treatment area, where the inner chamber includes a seconddecontaminating gas, where said second gas in said inner chamber is overpressurized with respect to atmospheric pressure, and where said outerchamber is also depressed with respect to the inner chamber.
 4. Machineaccording to claim 3, wherein said second chemical decontaminationtreatment area for applies to said sheet web a liquid that is chemicallyactive as a decontaminating agent.
 5. Machine according to claim 4,wherein said second area comprises a submersion tank containing saidliquid and a guide that introduces said web into said tank so that saidliquid is applied by immersing said web in said liquid.
 6. Machineaccording to claim 4, wherein said second area comprises a firstdecontamination compartment which houses a first sprayer and a guidethat introduces said web into said first compartment so that said liquidis applied by spraying said liquid onto said web.
 7. Machine accordingto claim 3, wherein said first gas in said first area is overpressurized with respect to the pressure in said inner chamber. 8.Machine according to claim 1, wherein said first area is overpressurized with respect to atmospheric pressure between 5 and 500 Pa.9. Machine according to claim 3, wherein said second chemicaldecontamination treatment area uses a third gas that is chemicallyactive as a decontaminating agent.
 10. Machine according to claim 1,further comprising: a plurality of access points on a same side and saidouter chamber surrounds said machine only on said side.
 11. Machineaccording to claim 1, further comprising: top stoppers and a secondchemical decontamination treatment area for applying to said stoppers aliquid that is chemically active as a decontaminating agent.
 12. Machineaccording to claim 11, wherein said second area comprises a submersiontank containing said liquid and a guide that introduces said stoppersinto said tank so that said liquid is applied by submersion.
 13. Machineaccording to claim 11, wherein said second area comprises adecontamination compartment which houses a sprayer and a guide thatintroduces said stoppers into said compartment so that said liquid isapplied by spraying said liquid onto said stoppers.
 14. Machineaccording to claim 1, wherein said packaging comprises top stoppers, andan area for attaching said stoppers to said packaging, wherein saidstopper attachment area comprises a first area for prewelding thestopper to the sheet material, a second area for welding the stopper tothe sheet material and a third area for welding the sheet materialarranged on the sides of the stopper.
 15. Machine according to claim 2,further comprising: a second chemical decontamination treatment areawhere a second treatment area is arranged before the preforming area;and an inner chamber that extends between said second treatment area andsaid first treatment area, where the inner chamber includes a seconddecontaminating gas, where said second gas in said inner chamber is overpressurized with respect to atmospheric pressure, and where said outerchamber is also depressed with respect to the inner chamber.